This invention relates to semiconductor devices, and in particular, to insulated gate type field-effect transistors, and to the formation of integrated circuits consisting of such transistors.
Conventional insulated gate field-effect transistors cannot provide the high-speed operation and low power dissipation desired. This results from the limited frequency dependence of the known devices caused by the superposed feedback capacitance between the gate electrode and each of the source and drain. Further, the width of the source and drain in the conventional insulated gate type field-effect transistors is limited by the accuracy of photo-etching and is such as to make difficult integration of a large number of such transistors. Further, the width and length of the source and drain greatly increases the junction capacitance of the device, preventing high speed operation and low power dissipation. By using a polycrystal silicon doped with impurities as a diffusion source and as an electrical conductor, the foregoing difficiencies have been avoided.